The strain used to be classified as Saccharomyces cerevisiae based on traditional taxonomic characterizations, but a recent molecular authentication convincingly identified it as Saccharomyces kudriavzevii, not S. cerevisiae. The taxonomic update of this strain will not affect its application in antifungal drug testing assays and many other usages. RefSuh SO, et al. Update of USP drug testing reference strain ATCC® 2601™. Pharma. Microbiol. Forum Newslett. 19: 4-11, 2013.